Spark-plug.



E. T. McCALL.

SPARK PLUG.

APPLICATION FILED MAY 15, 1915.

Patented Sept! 4, 1917.

- Inventor Attorneys I (ZZZ f w @YK UNITEI) STATES PATENT OFFICE...

EDWIN TJMCCALL, OF LAURIHBURG, NORTH CAROLINA.

srAn -rnue.

Application filed May 15, 1916.

To all whom it may concern:

Be it known that I, EDWIN T. MoQALL, a citizen of the United. States, residlng at Laurinburg, in the county of Scotland and State of North Carolina, have lnvented a new and useful sparkePlug, of which the following is a specification.

The deyiceforming the subject matter of this application is a spark plug, and one object of the invention is to provlde novel means whereby carbon will be prevented from accumulating on the electrodes of the spark plug. c

Another object of the inventlon is to provide novel means for priming'an internal combustion engine through the spark plug.

It is within the province of the disclosure to improve generally and to enhance the utility of devices of that type to which the present invention appertains.

lZVith the above and other objects in view which will appear as the description proceeds, the invention resides in the combination and arrangement of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the invention herein disclosed can be made Within the scope of What is claimed, without departing from the spirit of the invention.

Tn the accompanying drawings Figure 1 shows in longitudinal section, a spark plug embodying the present invention;

Fig, 2 is a cross section on the line 2-2 of Fig. 1; and

Fig. 3 is a fragmental side elevation showing the lower end of'the spark plug, parts being broken away.

The spark plug forming the subject matter of this application includes a tubular body 1 threaded as shown at 2 to cooperate in the usual manner with the cylinder of an internal combustion engine. The spark plug body includes an annular foot 3 connected bydepending arms 33 with the body portion of the plug. The numeral 4: designates an archedelectrode bulgedupwardly intermediate its ends as shown at 5, and having its ends mounted in the annular foot 3. The foot 3 may be dentedas shown at 50, to hold the electrode in place.

The numeral 16' indicates an insulating neck inserted into the body 1 and provided intermediate its ends with a laterally pro- Specification of Letters Patent.

Patented Sept. 1, 1917. Serial No. 97,587.

jecting rib 7 cooperating with a shoulder 8 formed in the interior of the body 1 and (:0- operating with the lower end of a tubular nut 9 threaded into the upper end of the body 1. 'Interposed between the rib 7 and the lower end of the nut 9, and disposed between the shoulder 8 andthe rib 7 are gaskets 11. At the lower end of the insulating neck 16 is fashioned a chamber 12 communicating with a reduced bore 35, the elements 35 and l2resulting in the formation of a shoulder 1% in the neck 16.

Disposed in the bore 35 of the neck 16 is a tube 15 provided intermediate its ends with a head 16 -coacting with the shoulder 14-, a washer 17 preferably being interposed between the head and shoulder. The lower end of the tube 15, is fashioned into a depending electrode 18. The tube 15 is provided with a priming bore 19 having a lateral outlet 20 located in the head 13 and discharging into the chamber 12 formed in the iower end of the neck portion 16 of the plug. In the upper end of the tube 15 there is formed a seat 62. A nut 21 is threaded onto the upper end of the tube 35. A washer 22 is interposed between the nut 21 and the upper end of the neck 16. When the nut 21 is tightened up the head 16 of the tube 15 coiiperates with the shoulder 14in the neck 16 and thus the tube is held securely to the neck. Threaded onto the upper end of the tube 15 is a nut 23 and between the nuts 23 and 21, the end of a conductor 2 1 is bound.

Threaded onto the upper end of the tube 15 is a cup 25. The lower portion 46 of the cup may, if desired, be fashioned with wrench faces, so that the cup 25 may be threaded down to a firm seat on the nut 23. Threaded into the cup 25 is a cap 26 having an opening 2? in its side and a top vent 65. The cap 26 may carry a binding post 60. The cap 26 may have a depending stem 63, embodying a pointed end 6% fitting in the seat 62 and closing the bore 19 of the tube 15 when the cap 26 is rotated and moved downwardly.

Mounted to reciprocate vertically within the contour of the annular foot 3 of the body 1 of the spark plug is a striker which may be fashioned variously. Preferably,the striker includes a body 28 made ofinsulating material, such as porcelain, although anyinsulating material may be resorted to if desired. Extended through the body 28 of the striker is a conducting member which.

4 may be made as the exigencies of the proposed use demand. In the present instance, a disk 29 is superposed on top ofthe body, a disk 30 is applied to the lower end of the body, and the disks are connected by a conducting securing element, which may be a rivet 31.

In practical operation, the. striker comprising the body 28 and parts carried thereby, reciprocates between the electrode 4 and the electrode 18, and these elements are thus kept free from carbon deposit. i The cap 26 may be threaded upwardly in the cup 25 until the opening 27 appears above the upper edge of the cup, whereupon gasolene may be squirted into the cup 25 through the opening 27, the gasolene traversing the bore 19 of the tube 15 and ultimately being discharged through the outlet 20 into the chamber 12.

Although the cap 26 may be dispensed with if desired, the cap, when employed in the manner hereinbefore mentioned, serves to prevent foreign matter from entering the cup 25, the opening 27 being visible only when the cup has been elevated to the dotted line position shown in Fi 2. Owing to the fact that the bore 19 o terminates in the lateral outlet 20, the priming charge of gasolene is deposited in the chamber 12 to one side of the electrode 18 and does not come in direct contact therewith, an unnecessary depositing of carbon on the electrode thus being avoided.

the tube 15 The stem 63 closes the bore 19 of the tube 15 and prevents damage due to an explosion of any gasolene which may happen to remain in the cup 25.

Having thus described the invention, what is claimed is 1. A spark plug comprising a body, an annular foot, an arm connecting the body with the foot; a first electrode carried by the foot and extended beneath the foot; a second electrode disposed within the body above the foot; and a striker mounted to reciprocate within the foot, between the electrodes.

2. A spark plug including a body, an annular foot, an arm connecting the body and the foot; a U-shaped electrode having both of its ends mounted in the foot; a second electrode disposed within the body above the foot; and a striker mounted to reciprocate within the foot between the electrodes, the striker including" an insulaing element, conducting members adapted to cooperate with the respective electrodes; and a conducting connection uniting the conducting members and passing through the insulating element.

In testimony that I claim the foregoing as my own, I have hereto afiixed my signature in the presence of two witnesses.

EDWIN T. MoCALL. Witnesses v G. E. Moss,

J. T. COVINGTON. 

